This application relates generally to air bags for vehicles. More specifically, this application relates to a diffuser for diffusing inflator gas during deployment of an air bag.
Air bags have become common in modern automobiles. An air bag module including an inflatable cushion and an inflator is installed in the desired position within the vehicle. The cushion is stored in a folded position within the air bag module. In response to a threshold event or occurrence, a sensor provides a signal for activating the inflator. The inflator provides a supply of inflating gas to the cushion to inflate the cushion.
There are several types of inflators for air bag modules. One type is the pure gas inflator wherein a pressure vessel contains stored pressurized gas. The pressure vessel communicates with the cushion through various types of rupturable outlets or diaphragms. Another type is the gas generator wherein a propellant is ignited and the resultant gas flow through an outlet to the cushion. A third type is the hybrid or augmented type. This type includes a pressure vessel containing stored pressurized gas and a gas generator. When the generator is ignited, the resultant gas flows with the stored gas to the cushion through the pressure vessel outlet.
Tethers within the cushion have been used to limit the rearward excursion and biasing of the air bag cushion. As used in this application, rearward excursion is expansion of the air bag cushion inboard of the vehicle in a centralized manner and biasing is for the expansion of the cushion off center or in a particular direction. Thus, tethers provide for reduction or set a limit for rearward excursion and provide for a reduction or limit in the biasing of the cushion.
An air bag module including an inflator, a cushion, and a flexible diffuser is provided. The inflator generates an inflator gas for deploying the cushion. The flexible diffuser is folded to a generally parachute shape for diffusing the inflator gas during deployment of the cushion.
An air bag module including a cushion and a diffuser is provided. The cushion is expandable radially and rearward of the air bag module. Similarly, the diffuser is expandable radially and rearward of the air bag module and is disposed in the cushion. The diffuser includes at least one vent in fluid communication with the cushion. An inflation gas exhaustible into the diffuser deploys the cushion. The inflation gas expands the cushion and the diffuser rearward to a first predetermined distance. The vent is positioned downstream of the interior surfaces when the diffuser is at the first predetermined distance. The inflation gas is diffused by the diffuser through the vent to radially expand the cushion after the rearward expansion to the first predetermined distance. The cushion is further expandable rearward to a second predetermined distance after the radial expansion of the cushion.
A rectangular diffuser in an air bag cushion is provided. The rectangular diffuser includes a pair of minor edges, a pair of length-wise edges, and a fold. The fold approximately bisects the pair length-wise edges such that the pair of minor edges are adjacent one another. The fold forms a pair of sealed top corners at the fold and an opening at the minor edges. A curved seam is sewn at the pair of top corners. Vents are positioned in the diffuser downstream of the interior surfaces.
A box shaped diffuser in an air bag cushion is provided. The box shaped diffuser includes a flexible material having a first edge, a second edge, a third edge, a fourth edge and four corners. A vertical fold line approximately bisects the first edge and the second edge, forming left and right sections of each of the first and second edges. Similarly, a horizontal fold line approximately bisects the third edge and the fourth edge, forming upper and lower sections of each of the third and fourth edges. A diagonal fold at each of the four corners is sealed with a corner seam. An opening formed at the corner seams by sealing: (1) the left section and the right section of the first edge to one another with a first seam; (2) the left section and the right section of the second edge to one another with a second seam; (3) the upper section and the lower section of the third edge to one another with a third seam; and (4) the upper section and the lower section of the fourth edge to one another with a fourth seam. Vents are positioned in the diffuser downstream of the interior surfaces.
The above-described and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description, drawings, and appended claims.